


Gambler's Fallacy

by shotabootyshorts (vegetables)



Category: Big Hero 6 (2014)
Genre: Anal Sex, Established Relationship, Incest, M/M, Oral Sex, Public Sex, Sibling Incest, Smut
Language: English
Status: Completed
Published: 2020-06-23
Updated: 2020-06-23
Packaged: 2021-03-04 00:00:38
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 7,249
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24874252
Author URL: https://archiveofourown.org/users/vegetables/pseuds/shotabootyshorts
Summary: On Hiro's 15th birthday, Tadashi keeps an old promise to teach his younger brother how to drive. Thirty minutes into the first lesson, the truck is wrapped around several trees. Hiro blames a faulty emergency brake. Tadashi blames the blowjob.
Relationships: Hiro Hamada/Tadashi Hamada
Comments: 2
Kudos: 150





	Gambler's Fallacy

“Learning to drive is a big deal, dude. It means you’re, like, a _man_.”

Hiro frowns at Fred from across the lunch table. “My aunt said the same thing when I turned thirteen.”

“Oh, yeah, thirteen is super cool—but, actually, sixteen is the real deal,” Fred assures with a nod. “My parents threw me a _huge_ bash when I turned sixteen. Got me a car and everything. I bet you can’t wait for that, next year.”

Wasabi tries to be tactful. “Not all of us are as—um, privileged, Fred.”

“No kidding,” Gogo says. “I was already working three jobs by the time I turned sixteen—and, that was just to _save up_ for a car.”

The loud suctioning noise from Fred’s straw makes an abrupt stop, and he sets down his soda. “You mean, you guys _didn’t_ have a super Sweet Sixteen extravaganza?”

“It’s not really that common,” Honey confesses. “Oh! But, I do have some photos from my _quinceañera_ , if you’d like to see them, Hiro.” She’s already pulling out her phone and navigating toward various social media apps.

“You’re just lucky you get to start learning at fifteen,” Gogo says. “But, I hope you have other plans for your birthday that don’t involve being stuck in a car all day.”

“It’ll only be for a few hours,” Tadashi says, briefly glancing at Honey’s phone, which Hiro is currently holding. “Driver’s ed can get pretty boring. Even if your instructor is your cool older brother.”

Hiro raises a doubtful brow toward Tadashi, then continues to swipe through photos of a fifteen year-old Honey Lemon dressed in an aqua-colored dress, complete with a beaded bodice and an obnoxious bubble skirt. They’re not the most flattering images.

“That should be fun,” Wasabi says; “but, how are you going to teach him? You just have the Vespa.”

Hiro hands the phone back to Honey. “Aunt Cass said we could borrow the truck,” he answers.

“That thing is ancient,” Gogo says with a grimace. “Do your aunt a favor and wreck it.”

* * *

On the morning of Hiro’s fifteenth birthday, he wakes up to the sound of rain pelting against the attic’s windows. It’s oddly cold in their bedroom, and he does all that he can to burrow deeper into his comforter, especially after he sees it’s not even eight o’clock yet. He dozes off for another ten minutes, then peeks out from the sheets when he hears Tadashi walking around on the creaky floorboards.

“You’re awake,” Tadashi acknowledges, but Hiro just groans.

Tadashi wishes him a happy birthday, and there’s probably a gorgeously vibrant smile on his stupid face, but Hiro’s too busy rolling over and grumbling. After brushing his teeth, Tadashi wanders over to his little brother’s bed, carefully sliding under the blankets and pulling him close.

“Excited to drive?” Tadashi asks.

“ _Mm_ , not really,” he mumbles. He scoots over and buries his face into Tadashi’s neck. “This is so much better. Let’s just do this all day.”

Tadashi kisses the top of his head. “We really ought to get an early start,” he suggests.

Hiro still looks drowsy as he pulls away, but there’s a nefarious spark in his subsequent grin; predictable, really.

“Boys? Are you awake?”

Aunt Cass’s voice is an echo, heard far down the flight of stairs and coming from the kitchen. Tadashi shifts against the mattress the way he always does in his paranoia, then calls out a response. It’s enough to prompt Hiro to roll out of bed, but he remains miserable about the whole ordeal, trudging to the bathroom with bleary eyes and disheveled hair.

Downstairs, Aunt Cass is as energetic as ever. Tadashi doesn’t ask for confirmation, but she appears to be on her third cup of coffee, and she’s setting the table with a spring in her step. There’s a small pile of presents over by the living room, along with a modest birthday banner. It’s clear she’s been careful as to not embarrass the birthday boy with too many decorations. For weeks, Aunt Cass had been persistent in her offers to close the café for the day, but Hiro modestly declined, reassuring his aunt that they would have plenty of time to celebrate once the shop was closed.

“Remember, Tadashi, you are _not_ to let Hiro drive anywhere but on the campus,” she reminds him.

Tadashi takes a sip of his orange juice and nods. “Don’t worry. I’m prepared for any and all tricks Hiro is bound to pull.”

When said birthday boy finally emerges, Aunt Cass rushes over to him, blubbering celebratory wishes and fussing with his bedhead. She proclaims he already looks at least an inch taller and that it’s a good thing she’s kept all the receipts to his presents, especially the one to the blue turtleneck that he’ll look _so cute_ wearing this winter.

“There goes that surprise,” Hiro says.

“Do you want anything special, for breakfast?” she offers. “Pancakes? Okayu? Eggs?”

It’s remarkable how she’s always up for cooking well-balanced meals, but Tadashi politely declines and assures they’ll be satisfied grabbing some muffins from the café.

“All right,” Aunt Cass concedes. She’s still primping Hiro, who’s being a surprisingly good sport about the whole affair. With exasperated sentimentality, Aunt Cass places a hand over her chest and stares at Hiro in awe. “Fifteen. My little man is growing up so fast.”

Hiro smiles, reluctantly. “Please, don’t cry,” he requests.

“Just be careful today, okay?”

“Don’t worry, Aunt Cass,” Tadashi says. “We’ll be fine—and, I promise we’ll be home to help for the afternoon rush.”

* * *

Hiro is still yawning when they pull into the SFIT parking lot. He thinks, really, it should be a federal crime to be awake this early—especially when it’s your goddamn birthday. He rubs his eyes to clear his vision, then glowers at the row of silk ficus trees surrounding the damp parking lot. He decides their broken branches and discolored leafs are truly symbolic for the agony he is currently facing.

But, Tadashi is all bright spirits as he switches off the truck and gives one of those sideway smiles that warns Hiro his brother is about to get _super_ geeky.

“Are you excited?” Tadashi asks.

“Mildly.”

“Let’s start from the top,” Tadashi says. He pulls back the bench seat. “You’re going to need to adjust your seat properly so that you can reach the pedals. Make sure your knees aren’t bent. Adjust your mirrors, too.”

Hiro makes some kind of unenthused noise, then yawns.

“As for the pedals,” Tadashi continues, shifting his legs beneath the steering wheel to give Hiro a view of the floor; “the right one is, of course, the accelerator, and the left is the brake, and the one to the far left is the parking brake.”

“ _Jesus_ , Tadashi, I know that.”

Tadashi removes the key from the ignition and prepares to give a proper demonstration. “Now, when you put your key in the ignition and turn it, the first click is going to turn on the lights, and the second is going to start the engine.”

“ _Fuck_. I know that, too. Can I drive, now?”

“No, Hiro,” Tadashi states as he starts up the truck again. “You have to listen, okay? This is important.”

Hiro sighs but, ultimately, scoots a bit closer on the bench seat, giving Tadashi his full attention.

“Once you start the car, you’re going to release the brake, then put the car in drive. So, you want to press down on the parking brake and pull this tab until you hear a click. Now, before you put the gear in drive, you should probably get a feel for the accelerator. Understand the pressure.”

Tadashi drones on for about ten more minutes as he drives around the parking lot, demonstrating slow turns and braking. He finally pulls back into a parking space and shuts off the engine, breathing a nervous sigh as he looks over at his younger brother.

“Okay—are you ready?”

Hiro basically shoves Tadashi out of the truck so he can slide into the driver’s seat. Reluctantly, Tadashi makes his way over to the passenger side. It already looks so foreign and _wrong_ to see his baby brother behind the wheel. Hiro’s about three sizes too small for the vehicle. Maybe they _should’ve_ waited until he was sixteen, Tadashi thinks. But, it’s a little too late, now, considering Hiro has already started the truck again and is busy adjusting the rearview mirror.

Surprisingly, Hiro does as Tadashi instructs by testing out the accelerator. He revs the engine, then adjusts the mirrors. He’s just about to pull the car forward when Tadashi stops him.

“Wait, you knucklehead!” Tadashi exclaims. He leans over his brother, pulling the forgotten seatbelt over his brother’s chest.

“Oh, _come on_ , Tadashi,” Hiro complains. “It’s not like I’m going to be speeding down the highway.”

Tadashi doesn’t look amused. “Hiro, seatbelts save lives. Buckle up—every time.”

“Fine, fine,” Hiro says, straightening the strap before he puts the gear in drive.

Tadashi settles in his seat. It’s somewhat unnerving to be in a car with a new driver. Especially when that new driver is your reckless, impulsive younger sibling. But, Hiro has a determined gleam in his eye, like he knows this is going to be a piece of cake. 

“Just tap the accelerator a bit to pull forward,” Tadashi instructs.

Hiro nods. They drive around the parking lot for a while, testing out the leveled ground and open space. Hiro shows no anxiety for a first-time driver. He doesn’t clutch the wheel until his knuckles are white, and he doesn’t lock his elbows every time he makes a turn. Tadashi almost wants to ask if he’s done this before. He and Gogo have been spending a lot of time together, after all. 

Eventually, Tadashi decides Hiro is ready to drive through the campus. They pass the library and robotics lab, both of which are desolate on a Saturday morning. When they reach the cafeteria, Hiro drives up the hill with ease before Tadashi points ahead of them and tells him to pull over.

“Okay, park there, and I’ll show you how to reverse.”

Hiro nods and does as he’s told.

“Good,” Tadashi says, an exhale quickly following. The tightness in his chest quells as Hiro parks the car. 

“Why are you so _tense_?” Hiro asks. “I mean, sure, your life is essentially in my hands, but I’m not sure I appreciate this lack of trust, bro.”

“I know—I’m sorry,” Tadashi breathes. “You’re doing great. Really. You should’ve seen Aunt Cass when she taught me. I think she grabbed the wheel from me a total of nineteen times because she thought I was going to murder a dog by driving too close to the curb.”

Hiro laughs. “Remember when we were kids and that pigeon flew into the windshield, and she thought she killed it and swore she was never going to drive again?”

“Yes, I do,” Tadashi replies. “We had to take the cable car to school for a month because she refused to drive us.”

Aunt Cass had soon realized the inconvenience of not driving and, thus, she started feeding the pigeons outside the café as vindication. At some point, an animal welfare group sent her a threatening letter that detailed the correlation between pastries and bird obesity.

“That seems like decades ago,” Tadashi says. “And, now look. I’m teaching _you_ to drive.”

Hiro makes a thoughtful noise and glances over at his brother, who shares a similar reminiscent expression. It’s moments like this that remind Hiro he’ll always see Tadashi as his brother, first, and his lover, second. It’s abnormal, sure, and debatably totally fucked up, but Hiro often wonders how two people from two completely different walks of life can come together and form an intimate relationship. He doesn’t think he’d like that very much. He wants someone who knows everything about him. Someone who shares all his memories. Tadashi is his equal. His everything. And, right now, with that warm smile and soft gaze, Tadashi looks so stupidly _gorgeous_ that Hiro wants to scream.

“What?” Tadashi asks, catching his brother’s look.

Hiro just smirks as he shuts off the engine and unfastens his seatbelt.

“What are you doing? Put that back on.”

Hiro laughs and slides over to his brother. He comments about how this is exactly why bench seats will always be superior to bucket seats, then leans in close.

“You said I did well. So, you should reward me, right?”

Tadashi quickly scans the hill’s perimeter before he complies to a brief kiss. It may be a Saturday morning on a college campus, but that doesn’t give them the clear for PDA.

“That didn’t seem sincere,” Hiro grumbles.

Hiro keeps their eyes leveled and pulls in his lips, the smallest of pouts forming. It’s the look he knows Tadashi can’t resist, the look that even makes Aunt Cass struggle when she’s supposed to be scolding him. Long ago, she admitted her nephew made it almost impossible for her to punish him with those doe eyes and full lips; it didn’t take long, after that, for Hiro to learn how he could use his features to his advantage. Hiro’s fairly certain poor Aunt Cass never had _this_ in mind, but it doesn’t matter much when Tadashi is already breaking. The pout is replaced with an impish smirk as he slides his hand down his brother’s chest, eyes still locked.

Hiro thinks this is a way more entertaining rite of passage than learning how to drive.

He starts to move down, loosening Tadashi’s belt on the way; but, before he gets a chance to pull at the zipper, his brother stops him.

“Hiro,” he warns; “this isn’t a good idea.”

“But, it’s my birthday.”

Tadashi’s bottom lip disappears as he tries to stay grounded. “That’s not a very good argument. With that logic, shouldn’t I be doing something... for you?” He frowns at his own words, because it’s not necessarily the defense he intended.

“This is for me, though,” Hiro argues. “I like sucking your dick.”

“We shouldn’t be doing this in the car,” Tadashi continues, urging the younger boy back up. “It’s public indecency.”

Hiro waves a dismissive hand just before he unbuckles Tadashi’s seatbelt. “I hope you know you’re literally the only idiot on this planet who would say no to a blowjob.”

Tadashi is about to refute that, but Hiro cuts him off with another kiss. It’s heated, this time; more thorough. Hiro slides his tongue into his brother’s mouth and moans against the kiss. Tadashi’s eyes stay open the entire time, shifting in all directions as he searches for bystanders. _No one._ Just bike racks and picnic tables and those goddamn ficus trees. Hiro pulls away, only to press his face into Tadashi’s shoulder and nip at the skin there.

“Come _on_ ,” Hiro urges. His hand traces the inner-seam of Tadashi’s pants. “We’ve never done this before, Tadashi. It’ll be _fun_.”

Tadashi grunts when Hiro gently squeezes at his dick. “Fine, but make it quick.”

“That’s sort of up to you,” Hiro reasons, beaming as he moves back down to continue his earlier work.

Hiro kneels on the bench seat, tugging at Tadashi’s zipper and dipping his fingers into the jeans. The heat beneath the fabric is encouraging. Tadashi is hard, and Hiro doesn’t hold back the satisfied smirk as he pulls his brother’s cock free, ready to take the entire length in his mouth before there’s a moment to protest.

“ _Mmm_.”

Hiro’s little murmurs are laced with lust. He loves how Tadashi’s cock feels beneath his fingers, heavy and throbbing. He traces the veins in routine admiration, then noses at the flesh. He knows how to tease, knows how to drive his brother absolutely crazy. Hiro’s tongue is quick to dart out and press against the tip, spreading the precome that leaks from the slit.

He looks up, intent on meeting Tadashi’s gaze before he wets his lips and lowers himself over his brother’s cock.

Above him, Tadashi moans. He tangles his fingers into Hiro’s hair, urging his brother farther down. It’s such a scene, Tadashi thinks, one that he’s always drawn into when Hiro’s jaw is stretched wide, cheeks hollowed out and flushed a deep red. Tadashi throws his head back in another moan, scattered swears quickly following.

Hiro withdraws and, teasingly, strokes Tadashi’s cock in his hands. “This isn’t really how I pictured it,” Hiro points out, smirking when he hears his brother hiss with frustration. “I kind of wanted you in the driver’s seat. A win’s a win, I guess. And, we can always do this again another time, too. Maybe make it a weekly thing. Although, if you want to switch places, now—”

“ _Hiro_...”

Tadashi’s tone is clipped. Hiro laughs, cruelly, and flashes a smile before he draws himself back over his brother’s dick. He takes as much as he can into his small mouth, teeth scraping only briefly against the flesh. Tadashi’s grip on his hair tightens, and Hiro feels his brother’s hips thrusting upward, desperate for more contact. He’s close. Hiro works faster, moaning around him. He’s setting a pace, now; his mouth and hand working in unison, coasting up and down, up and down, and—

—the car is moving.

Hiro pulls himself up at the same time that Tadashi exclaims a swear. There’s no time for either sibling to properly assimilate the situation before the truck collides into the many ficus trees. The front clip dents and splinters, and Hiro is sent flying into the dashboard, where his head connects with the windshield in a loud, deafening _crack_.

* * *

“How on _earth_ did this happen?” Aunt Cass exclaims. 

She has that hysterical, unhinged tone, the one that makes Tadashi’s shoulders sink, no defense effective against the verbal thrashing. Tadashi pictures nearby patients in the emergency room cringing at the shrieking voice and shielding themselves under their sterile-scented hospital bed sheets. Distantly, he’s almost positive he hears someone flat line.

“You’re supposed to teach driving on a leveled ground!”

Hiro itches at the dramatic bandage wrapped around his head. He can feel dried blood on the scratchy cotton, and he’s a bit light-headed, but he really just wants to go home and have his birthday cake. This lumpy hospital bed isn’t doing much for his physical or mental recovery.

“ _Well_?” their aunt presses.

“We, um—I did,” Tadashi tries to explain. He’s sitting on the foot of the hospital bed, having left the scene relatively unscathed, albeit a small cut on his hand from clearing the glass off Hiro. “He was doing really well, so I thought we’d drive more around campus, then we parked on a hill, and I was going to show him how to reverse, and—”

“A hill!” Aunt Cass shrieks. “Why wasn’t the parking brake on?”

Tadashi finds enough willpower to glare at Hiro.

“Hey, you were the instructor,” Hiro accuses. “You should’ve pointed out my fatal flaw. Also, wait, how are we all sure I _didn’t_ put the parking brake on? Maybe it’s just broken. I demand an investigation, Aunt Cass. My name must be cleared.”

“Hiro, this isn’t a joke!” Aunt Cass gasps. “You have a _concussion_ —you could’ve been killed. You wrecked the truck! And, don’t get me started on the damage you caused on your very own college campus. You destroyed three trees, Hiro. _Three._ ”

He frowns. “It’s not my fault we were the victims of SFIT’s obsession with artificial foliage.”

One of the nurses from before approaches the cubicle, pulling back the medical curtains and smiling brightly. “Well, the doctor says you two are in the clear,” she says, matter-of-factly. She hands a clipboard over to Aunt Cass. “We just need you to sign here, ma’am, and your boys can be discharged.”

“Oh, thank goodness,” Aunt Cass says. “Will Hiro need to miss any school to recover?”

“No, no, that shouldn’t be necessary—the birthday boy will just need plenty of rest for the next few days,” she instructs. “Keep track of any dizziness or head pain. Make sure he doesn’t overexert himself, and he should be fine. We’re going to need to see him in two weeks, just for a checkup.”

Aunt Cass nods. “And, Tadashi—you’re sure he’s okay?”

“Oh, yes,” the nurse explains, soundly. “He was exhibiting a bit of a panic attack when we first brought them in, but his heart rate is down, and he no longer has shortness of breath.”

Tadashi stands and thanks the nurse for her help as Aunt Cass finishes signing off on the discharge papers. Hiro continues scratching at his bandage, wondering what kind of cake is waiting for him at home.

The nurse smiles as she takes the clipboard back from Cass. “I’ll be right back with a wheelchair to help you outside, young man,” she tells Hiro. “Standard procedure.”

Aunt Cass lets out another sigh. “Well, who knows how long the truck is going to be in the shop,” she states. “I’m going to hail a cab. I’ll meet you two outside.”

“Sorry, Aunt Cass,” Tadashi says, his tone heavy with shame.

Hiro shifts in the hospital bed. “Oh—um, yeah, I’m really sorry, too; really, I am,” Hiro manages, weakly. It’s easy to brush off the severity of this until he realizes how he’s burdened his poor aunt _yet again_. “We’ll work off the damage on the truck. Promise.”

Aunt Cass’s expression finally softens as she looks at her two nephews. She leans in and kisses Hiro’s forehead, right over the bandage. “I’m just glad you two are okay,” she says. She turns to Tadashi and places a hand on his shoulder. “You did the right thing by immediately calling 911.”

Once they’re alone in the cubicle, Hiro looks at his brother, critically. “What she meant to say is, you did the right thing by putting your dick away.”

“I’m glad you find this so funny,” Tadashi remarks, folding his arms. “What part of having a concussion is amusing, to you?”

“It’s a _mild_ concussion,” Hiro corrects; “and, come on—this’ll be a great story, one day.”

Tadashi gapes. “And, to whom do you feel we can ever share the full details of this event?”

Hiro just shrugs but the jovial smirk does not disappear. Eventually, the nurse returns with the wheelchair. As she wheels him out, she once again outlines the proper recovery procedures and instructs them to change the head bandage twice a day. When they reach the curbside, where Aunt Cass is waiting with the cab, the nurse hands Tadashi a few generic pamphlets on concussions.

“I hope the rest of your birthday goes well, young man,” the nurse tells him, before turning back to Tadashi. “And, you—well, you’re quite lucky. It’s a mystery how your brother took most of the blow.”

Hiro gives a piercing laugh and climbs into the cab.

* * *

Back home, Aunt Cass and Tadashi put Hiro to bed. Their aunt insists everything will be fine and that they can postpone cake and presents for tomorrow. She fawns over him for a good ten or fifteen minutes and even peeks under the bandages, where she spots the large gash.

“I thought all these crazy trips to the hospital were over, now that you two were older,” she laments, but there’s a smile on her face. She starts fidgeting with the bandage again, apparently not pleased with its current position.

“Aunt Cass!” Hiro shrieks. “If you keep doing that, Mochi’s fur is going to fly up and get stuck to the wound. I could get infected and die!”

“All right, all right!” she concedes, standing from the bed. She does need to get back downstairs, anyway; it’s difficult not to fret when she leaves the café in the hands of the newly hired employees. “Tadashi, keep an eye on him. Make sure he doesn’t try to sneak downstairs to open his presents.”

“Of course, Aunt Cass,” Tadashi says, smiling.

Tadashi adjusts the blinds in the bedroom, keeping the sunlight out, as per a pamphlet’s instructions. Hiro watches him, intently. His brother is practically pacing, which is always a sign he’s nervous and flustered. Probably angry, too. Hiro senses a lecture coming. Tadashi looks tense. Years ago, this kind of pensive, brooding aura from Tadashi would’ve been the precursor to an embarrassing arousal, the kind Hiro would have to stomp down until he could get to the shower to jerk off to the fantasy of Tadashi yelling at him and shoving him on his knees.

Finally, Tadashi pauses in front of Hiro’s bed. “I can’t believe I let you unbuckle your seatbelt,” he says. He puts a hand to his face, in dismay of his own behavior. “God, and I let you unbuckle mine, too. What’s _wrong_ with me?”

Hiro looks skeptical about his brother’s chosen statement. “I wasn’t about to give you a blowjob with our seatbelts on.”

“You shouldn’t have been giving me a blowjob, at all,” Tadashi bemoans.

“You’re not being very nice to the birthday boy.”

“Hiro,” he warns.

“Look,” Hiro starts, his tone finally shifting; “I’m not going to apologize for trying to give you a blowjob. _Maybe_ I can apologize about almost killing us, sure, but I’m still blaming the emergency brake.”

It never ceases to amaze Tadashi how his younger brother lacks the ability to process danger. “What about Aunt Cass’s truck?” he asks. “You _are_ sorry about that, aren’t you?”

“Of course!” Hiro nearly yelps. “You know I don’t like burdening her.”

There’s sincerity in that statement, much to Tadashi’s relief. He takes a moment to eye his brother for any impending smart ass remarks, then exhales. “Okay,” he concludes, figuring he’s lectured his brother enough. “I’m going to take a shower.”

Hiro makes some kind of offended noise and glares at Tadashi. “ _What_? Aren’t you going to comfort me? Or, better yet, we can continue where we left off before, you know, that mishap.”

Tadashi retrieves one of the pamphlets from his back pocket. “Not a good idea,” he says, methodically. “This says patients should refrain from sex for at least 48 hours. It could cause head ache and fatigue.”

“Wow, no birthday sex? Okay, this is, quite possibly, the worst birthday, ever.” Hiro pauses for a moment before he suddenly brightens. “Wait, can I still give you a blowjob?” he asks, somewhat hopeful.

“Sorry, Hiro, I’m going to bargain that blowjobs could possibly induce more head trauma.”

“Well, _now_ you’re talking, bro.”

“The answer is no.”

Hiro deflates. “Just go take your shower,” he grumbles.

With an annoyed huff, Hiro pulls his blanket over his body. His pout, combined with the theatrical bandage wrapped around his head, makes him appear properly miserable and defeated. He makes a point not to watch Tadashi start stripping off his clothes before he disappears into the bathroom.

The shower faucet spurts to life, and Hiro curses under his breath as he settles himself against the pillows. His head is only mildly throbbing, like a dull headache, but he’s more tired than anything else. He digs his phone out of his pocket and finds various messages that wish him a happy birthday. Fred’s message is abbreviated to the point of being nearly indecipherable, and both Wasabi’s and Gogo’s are straight to the point. Honey’s is the most enthusiastic. 

> Feliz cumpleaños, Hiro! ﾟ✿ヾ╲(｡◕‿◕｡)╱✿ﾟ What did you get?! ♥  
>  Sent at 10:23 a.m.

He considers not responding until the morning; but, if Tadashi is going to ignore him, he may as well find his sympathy elsewhere.

> A concussion.  
>  Sent at 3:13 p.m.

His phone rings immediately after, and he answers to tell her the story. 

The abridged story, of course.

* * *

Tadashi didn’t think anything could be more painful than Aunt Cass’s ear pulling. Unfortunately, he was wrong. A violent thrashing from Honey Lemon’s hefty purse is, by far, much worse.

“You could’ve killed him, Tadashi!” she exclaims, whopping him over the head with her bag for the third time. “On his birthday, too!”

Tadashi shields his face. “I know, I know!” he says. “Believe me, I feel horrible about it.”

Honey resigns from abusing Tadashi as she bends down to inspect Hiro’s face. “Are you sure you should be at school?” she asks, gently touching the bandage on his forehead. Hiro eats up the attention. “Even a mild concussion is serious, Hiro.”

“I’ll be okay,” he sighs out, but it’s just melodramatic enough to sound like it’s a strenuous effort to even be alive after such trauma. “And, don’t worry, I already reminded Tadashi that he’s a terrible brother.”

Wasabi’s brows are raised high as he folds his arms, baffled by the whole thing. “Listen, little man, I’d be happy to take you out for a lesson or two.”

“Do you really want to learn how to drive like an 80 year-old?” Gogo asks Hiro.

“Well, _you’re_ not teaching him,” Tadashi interjects, to which Gogo quickly flips him off.

Honey worries her lip and says: “It might be best to lay low on the driving, for now. This could be a very traumatic experience, for Hiro. He might flashback to it every time he climbs into the driver’s seat.”

“This is true,” Hiro agrees. The look he gives Tadashi is strangely smug. “In fact, I might need therapy.”

Gogo rolls her eyes and ushers Tadashi away. She reasons her latest project is far more interesting than Hiro’s tragedy. Tadashi agrees.

* * *

After classes, Hiro and Tadashi stop for ramen.

“Accident aside, I do hope you had a good birthday,” Tadashi says. He picks at his fried egg and watches as the yolk spills into his broth. “I’d feel really terrible if your birthday was a complete bust.”

Hiro’s smirk is lopsided, and it’d be easy to mistake it for aloofness, but Tadashi knows better. His brother only smiles like that when he’s flustered.

“It was fine—don’t worry.”

Yesterday’s belated birthday bash was as routine as Hiro desired. They had cake, Mochi bellowed, loudly, at the sight of fifteen small, open flames, and Hiro got a set of new tools, the blue turtleneck, and several books that Tadashi and Aunt Cass thought he might like. Aunt Cass also gave him 15,000 yen, which, despite his clamors about how she should just keep it, considering the truck repairs were guaranteed to be at least triple that, she insisted he take the money. He slipped half of it back into her wallet, later that night.

“By the way,” Hiro then says, his mouth stuffed with ramen; “it’s _officially_ been 48 hours. I noticed just before we left school.”

Tadashi watches his brother gulp down the noodles and smile, expectant. “That may be so, but I still think you should take it easy for a while.”

Hiro snorts. “What, do you think I’m going to have such a powerful orgasm that my head will explode? You sure think highly of yourself, Tadashi.”

“Keep your voice down, smart ass,” Tadashi tells him.

“It doesn’t really matter, anyway,” Hiro then says, pointedly. He continues to eat his ramen. “I mean, nothing is going to top car sex, and we don’t have a car, now. So, we might as well forget it, because there’s nothing new and exciting about you banging me in our bedroom.”

“You’re not really earning any points here, the way you keep insulting me.”

“Look, I’m just saying: If you want to keep your catamite happy, you should start thinking more outside the box.”

Tadashi nearly drops his chopsticks. “Hiro, I _beg_ you never to use that word again,” he croaks out.

Hiro just laughs and continues with his meal.

* * *

The truck is ready by Wednesday. Aunt Cass agrees to let Tadashi pick it up from the shop on the strict condition he doesn’t let Hiro anywhere behind the wheel. It’s the easiest promise Tadashi has ever made.

They take the cable car to the shop and, on the way home, Hiro is tortured by his older brother’s overly cautious driving. At every traffic signal, he slows down; at every stop sign, Hiro swears he can _hear_ Tadashi counting to three. Hiro groans. It’s actually unbearable—especially when Tadashi starts explaining traffic rules.

“Do you know what to do if there’s a traffic light out?” he asks.

“Call the police? Die? I don’t know.”

A sigh exudes from Tadashi as he rests his elbow on the window’s ledge and brings his fingers to his forehead. “You stop at the intersection, Hiro,” he explains. “You treat it as a four-way stop.”

“Yeah, well, you should also keep both hands on the wheel at all times,” Hiro shoots back. He slides closer to Tadashi, then—as close as his seatbelt allows. “You know, you might think not letting me ever drive again is devastating; but, quite frankly, it’s all the better, for me, because _that_ makes you my personal chaperone for all eternity.”

Tadashi scoffs. “As if. I _do_ have my own life, you know. My own friends.”

“No, you don’t. All your friends are also my friends, and they all like me better. Fred said so. By the way, you missed the turn.” Hiro looks over his shoulder and back toward the street they usually take home. When Tadashi says nothing, Hiro persists. “ _Hello_? You’re going the wrong way.”

“I just wanted to make a quick stop,” Tadashi tells him.

He can feel Hiro watching him, but Tadashi says nothing more as he continues to drive downtown. When Hiro starts to recognize some of the businesses, he inquires about _where_ exactly Tadashi needs to go. From the looks of it, they’re heading toward one of the seedier districts in town.

“ _You_ need to stop somewhere in Good Luck Alley?” he remarks, suspicious. “Bro, I think you might be the one recovering from the concussion, here.”

Once more, Tadashi remains quiet. He parks on one of the desolate, narrow side streets behind a car that has at least two punctured tires and a cracked back window. Tadashi turns off the engine and, despite the street being completely flat, he checks the emergency brake. Twice.

“If you’re going to kill me, Aunt Cass will know you did it,” Hiro points out. He sounds mostly unamused by the current situation. “The guy at the repair shop would also vouch.”

Tadashi has no response to that. He simply unbuckles his seatbelt and looks over at his brother.

“Come over here,” he says.

“Over where?”

“Here,” Tadashi repeats, gesturing. “On my lap.”

Hiro’s eyebrows shoot up. “ _What_ , really?”

There’s a pointed—no, impatient, actually—look from his older brother, and Hiro doesn’t need to be told twice. Or, three times, really. He quickly unbuckles his own seatbelt and crawls over to Tadashi. It’s easy to slide himself between his brother and the steering wheel. He always did fit so perfectly in his lap, like he was meant to be there. 

“Is this a belated birthday gift?” Hiro asks. He’s more than eager as he throws his arms over Tadashi’s body and pulls him close, lips and hands all over him. “You better not be pranking me. Like, we don’t _have_ to fuck, but you better at least jerk me off. Or, I can jerk you off. I’m not picky.”

Hiro palms at Tadashi, and his brother is hard. Already. He wonders just how incorrectly he’s been reading Tadashi for the past five days. His brother has been so goddamn _serious_ and particular, and Hiro chalked it up to guilt from several different facets of their complicated relationship. But, maybe it’s just been sexual frustration.

Hiro wants to laugh at him, except he knows he won’t get what he wants, if he does. So, instead, he goes quick: He tears at Tadashi’s belt, throwing it off to the side and reaching into his pants to feel his hard cock. He loves the sound his brother makes when his fingers wrap around his dick, when he strokes at it, inch by inch, before pulling it free from his denim. Just enough to achieve the necessary task.

Once Hiro slides off his own shorts, he gets the friction he wants by rutting against his brother’s cock. It’s a desperate little movement, totally novice, but Tadashi still groans and pulls Hiro closer.. They’ve gotten off plenty of times just like this before. And, for a moment, Tadashi thinks he might not have the stamina to last longer for anything else. Hiro small body can move so fucking _fast_ and nimbly. 

“Hold on,” Tadashi breathes. He readjusts himself on the seat and fishes in his back pocket to retrieve a condom—like he goddamn planned this, Hiro thinks—and, while both of them would prefer _not_ to use one, it’ll allow for easier cleanup. “Here.”

Hiro snatches it away and starts to rip it open. “You need to _hurry up_ ,” he mutters.

“You need to ask nicely.”

Hiro prickles with defense but says nothing. His fingers are coated with the messy lube from the condom, and it’s making everything very impractical as he tries to pinch the damn thing out of the foil.

“Ask nicely, Hiro,” Tadashi repeats; “or, we’re stopping and going home, now.”

Tadashi wouldn’t _dare_ , and Hiro knows it, because their resolve is _equally_ fucked; but, right now, Hiro is too needy, too compromised to fight, and he gasps out—“Hurry, Tadashi, _please_?” he begs—until, at last, Tadashi reaches to help secure the condom out of the foil. He slides it down over his cock, and Hiro’s fingers give his brother a few appreciative squeezes.

“I can’t believe you’re really going to _fuck me_ in here,” Hiro gasps out. He’s clinging to his older brother, getting all the contact he can manage. Their cocks briefly rub together, and the boy moans, loudly. “ _Fuck_ , Tadashi. Just do it, will you? Please.”

Tadashi laughs, darkly, and uses the excess lube to begin stretching Hiro open. It takes all the energy Hiro can muster to shift himself and provide better access for brother’s wandering fingers. He's tight but oh-so pliant, and Tadashi’s groans vibrate against Hiro’s ear when he leans forward and uses his mouth on the boy’s neck. Tadashi elects that three fingers are more than enough for his little brother and encourages Hiro to hover back over him.

If Hiro were more coherent, he’d pace himself. He’d sink down, slowly, onto Tadashi’s cock and revel in how his brother throbbed inside of him, thick and hot and making him feel so _full._ But, Hiro ran out of patience about five days ago, and he grabs hold of Tadashi’s shoulders to balance himself as he completely bottoms out onto his brother’s cock.

“ _Hiro_ ,” Tadashi groans. He grits his teeth and tries not to climax from that alone. “Holy shit.”

Tadashi absolutely _cannot_ move, or else he _will_ come within seconds. Hiro is just so goddamn tight, and he’s purposely clenching _hard_. He barely even gives himself enough time to adjust before he starts to move, fast: Rising up and immediately going back down. It’s amazing. It’s too good. And, it’s only when Hiro wraps his fingers around his own cock, working at it, desperately, that he starts to slow down.

Hiro is whining, moaning. He’s rolling his hips and trying to remain in control, but Tadashi is stronger and way more experienced at angling his little brother’s tiny body where he wants it.

“Harder,” Hiro demands. He pulls at Tadashi’s shirt and practically glares at him. “ _Please_ , Tadashi?”

Tadashi gasps, amazed by how Hiro’s boyish charm radiates even through his demands and impatience. They’re both so on-edge that their breathing turns into hot, wet pants, and the windows start to fog. Tadashi straightens his back and picks up his pace as he grabs at Hiro’s hips and pushes so hard into him that he feels his brother’s legs quiver. It’s then that Tadashi cries out and releases into the condom, wishing, so badly, it was inside of Hiro, instead. His vision goes blank and his muscles go lax, but Hiro comes just seconds later, into his small, clenched fist.

“ _Fuck_ ,” Hiro murmurs, helplessly, but it’s said with a dazed afterglow.

They’re both sweating and gasping for air, but Hiro still commands his lips against Tadashi’s. Even when Hiro pulls off and dismounts from his brother, he stays close. Tadashi removes the condom and ties it, but it’s Hiro who rolls down the truck’s window and tosses it onto the street, for him.

“Hiro,” Tadashi chides.

“What? It’s _definitely_ not the first used condom thrown onto Kabukicho Street.”

Tadashi doesn’t want to figure out how Hiro knows that, so he makes no further objections and focuses on readjusting his clothing. Hiro does the same and slides back into his shorts before collapsing against his brother’s shoulder.

“So, what changed your mind?” Hiro asks. “About the whole car sex and fucking me senseless, I mean.”

“I don’t know,” Tadashi admits. “Maybe you’re just that irresistible.”

“Well, I could’ve told you that.” Hiro kisses his brother’s cheek and displays his most charming smile. “So, can I drive home?”

Tadashi laughs, cruelly. “Nice try. Put your seatbelt on.”

* * *

“After _careful_ consideration, I have come to the conclusion that it’s simply better, for me, not to get behind the wheel of a vehicle until I do, in fact, turn sixteen.”

Gogo uses her fork to flick away one of the tomatoes in her salad. “Something tells me it might’ve been Tadashi who made that rule,” Gogo replies from across the table. “Nice try, though.”

“I’m getting real tired of people saying that, to me.”

“Actually, it was Aunt Cass’s decision,” Tadashi supplies.

Wasabi breathes in, deeply, as though he has been the one personally affected by the whole ordeal. “I’m relieved,” he says. “I don’t care what the State law says. I really don’t think it’s safe for anyone to get behind the wheel when they’re that young. In fact, sixteen is too young, if you ask me. It should _really_ be eighteen.”

“ _Guys_.” Fred appears at the head of the table and throws down a very greasy to-go bag from Yaki Taco. Honey Lemon discreetly pushes the foul-smelling thing farther away from her. “Someone else just crashed into the other row of ficus trees on campus.”

Gogo raises an eyebrow. “No way.”

“ _No_ , it’s true! Hiro, man, you started a revolution.”

“I really don’t think that’s what’s going on, here.”

Fred briefly considers the dispute. “Okay, well, one’s on fire, so that’s pretty cool.”

Honey Lemon grabs her phone from her purse before following Gogo and Fred out of the cafeteria. Fred shouts something about not eating his Yaki Taco, but Hiro already has his hand in the bag by the time they’re out of sight.

“I meant what I said before, Hiro,” Wasabi tells him. “When you’re ready, I’d be happy to teach you how to drive.”

“Thanks, Wasabi—I might take you up on that,” he says, unwrapping whatever it is that Fred ordered. “Tadashi distracted me too much.”

“I was a great teacher,” Tadashi defends. “You distracted yourself.”

“You’re the one who brought up running over dogs.”

“Yeah, and you started talking about Aunt Cass’s weird protect-the-pigeons phase.”

“You’re the one who got sentimental, Tadashi.”

“And, you’re the one who _looked_ at me.”

Wasabi blinks, then resumes eating his lunch. “You guys are weird.”


End file.
